NVIDIA seems to have lifted restrictions over manufacturers coming up with their own designs for the GeForce GTX 285 accelerator, barely a month into its market introduction. Zotac, backed by the engineering prowess of PCPartner seems to have already designed their custom-PCB according to a finding by Expreview. The new PCB employs a decent bit of component rearrangement.

Perhaps the most significant part of that rearrangement comes from moving the vMem circuit that powers the card's 16 memory chips to its anterior end, in between the NVIO2 processor and the SLI connectors. The PCB uses a new MOSFET arrangement that groups them in a DPAK group. The vGPU circuit consists of 6 phases, and the vMem circuit 2. Zotac makes use of an aluminum support-brace around the G200b graphics processor, which serves as a safety measure for the GPU, minimizing the impact of PCB bending on the fragile ball-grid, especially with 55nm GeForce GTX 260 and GTX 285 lacking a back-plate that counters PCB bending. The orange-coloured DVI connectors make it distinctively Zotac. The SKU based on the new PCB may feature reference clock speeds of 648/2484/1476 MHz (core/memory/shader). Its cooler design remains unknown.

What is your opinion of a typical cooler mounting? Doesnt the brace on the rear side of the cooler stop bending of the PCB? It's been mentioned a few times now. Should we be concerned about PCB fatigue due to missing back-plates? Is there a risk... or is it just a difference.

What is your opinion of a typical cooler mounting? Doesnt the brace on the rear side of the cooler stop bending of the PCB? It's been mentioned a few times now. Should we be concerned about PCB fatigue due to missing back-plates? Is there a risk... or is it just a difference.

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The GPU brace minimizes the impact of bending on the GPU. For the same reason, NVIDIA used support-braces for the G80 GPU, in 8800 GTS, GTX and Ultra. The brace is optional since as you said, the reference cooler already balances tension on the PCB by having bolts almost throughout the PCB, though, there are manufacturers (for example Galaxy), who are designing coolers that are entirely dependent on the four mounts around the GPU. With the coolers weighing in 100s of grams, one may expect pressure on that part of the PCB. Hence, the support-brace. Ironically, the Galaxy card doesn't use one (maybe since the cooler requires the inner mount-holes around the GPU).